In several parts of Europe quite a trade is carried on in the way of buying and selling rare insects, chiefly the rare Alpine butterflies and moths. The instant the entomologist steps from his carriage, in the celebrated valley of Chamouni, with net in hand, whence he is known to be a papillionist, he is surrounded by half a dozen Savoyard boys, from the age of fifteen down to eight, each with a large collecting-box full of insects in his hands for sale, and with the scientist bargains for the insects that are found only on the mountains, and which these hardy chaps alone can obtain. There are again insect dealers on a larger scale, who live there, and have many of these boys in their employ; one of which wholesale merchants, Michel Bossonney, at Martigni in the Vallais, in the year 1829, sold 7000 insects, mostly of rare and beautiful species. Another dealer, on a perhaps still larger scale, is M. Provost Duval, of Geneva, a highly respectable entomologist. In 1830, he could supply upwards of 600 species of Lepidoptera, and as many Coleoptera, of the Swiss Alps, the south of France, and Germany, at prices varying from one to fifteen francs each, according to their rarity. The advantage of this new traffic, both to the individuals engaged in it and to science, is great. Now the _Sphinx (Deilephila) hippophaes_, formerly sold at sixty francs each, and of which one of the first discovered specimens was sold for two hundred francs, is so plentiful, in consequence of the numbers collected and reared through their several stages, by the peasants all along the course of the Arve, where the plant, _Hippophae rhamöides_, on which the larvæ feed, and the imago takes its specific name, grows in profusion, that a specimen costs but three francs. A general taste also for the science, and an appreciation for beauty, is spread by the more striking Alpine species, such as _Parnassius apollo_ and _Calichroma alpina_, not only among the travelers who buy them for their beauty, who before would hardly deign to look upon an insect, but among the more ignorant Alpine collectors themselves.[1254] Navarette, under the head of “Insects and Vermin,” speaks of an animal which the Chinese call Jen Ting, or Wall-dragon, because it runs up and down walls. It is also, says this traveler, called the Guard of the Palace, and this for the following reason: The emperors were accustomed to make an ointment of this insect, and some other ingredients, with which they anointed their concubines’ wrists, as the mark of it continued as long as they had not to do with man; but as soon as they did so, it immediately vanished, by which their honesty or falsehood was discovered. Hence it came that this insect was called the Guard of the Court, or, of the court ladies. Navarette laments that all men have not a knowledge of this wonderful ointment.[1255]